Interval Duration?

Gav888

Hi,

Im just adding the finishing touches to my new training plan and I wanted some advise regarding interval durations.

Firstly, what is the best interval duration for threshold and vo2max?

Are threshold intervals best at 2 x 20m in hr zone 4 or would 2 x 30m in zone 4 be better?
Are vo2max intervals best at 5 x 4m or would 5 x 5m or 5 x 6m be better?

From what ive been reading (which is alot) threshold intervals are always quoted as 2 x 20m to make the best gains, but in my new plan im including 2 x 25m and 2 x 30m as the year progesses and wanted to know if this is benefitial or should I keep them to 2 x 20m and just increase my output to make them progressive. Do these work best at 2 x 20m and anything longer is less benefitial?

For vo2max intervals, ive read that 4m intervals are best as it is such a narrow band you need to hit, anything less and you wont reach vo2max for long enough to make any gains, and any longer and you wont be riding hard enough to reach vo2max, is this correct?

Also for these, is it right that vo2max gains can only be made over a 2 - 3 week period and then it levels out?

And finally, for intervals such as 10 x 30sec max effort (spints) and 5 x 5m in hr zone 5, as these best used a few weeks before your goal to make sure you are in peak fitness - sort of the icing on the cake - or do you include these intervals throughout the year (excl winter base training) and progressively make gains?

Cheers

chrisw12

I'll have a stab at the 2x20 question. There's nothing special about the 20, it can be any long duration. The point is you are spending about 40 mins at you ftp (one hour power.)

Are you planning to do them on the road or turbo, because ime this will be the biggest factor effecting interval duration.

Brindy

With the interval length it is best to go shorter but be hitting target power/HR than be going longer and be below for last 5mins or end up feeling to terid the next day to train.

If you are doing true VO2 efforts you shouldn't be doing much longer than 3-4mins with at least 1-2x that in recovery

Gav888

Thanks for the replies, intervals will be on the turbo so I can make sure im hitting the right zones for the full amount of time.

terongi

chrisw12 wrote:

I'll have a stab at the 2x20 question. There's nothing special about the 20, it can be any long duration. The point is you are spending about 40 mins at you ftp (one hour power.)

Are you planning to do them on the road or turbo, because ime this will be the biggest factor effecting interval duration.

I'd agree with all that.

PLus - my understanding of the 2x20 for turbo training is that it is found to be the length of time most athletes can manage before dying of boredom.

I'm not sure what, if any, gains you would make by increasing the lebgth of those intervals if you can face the tedium.

Obviously, if you are unable to train for days afterwards then the session will have been counterproductive.

Anonymous

I find longer (i.e. over 10 min) intervals are bloody hard on the turbo.

I hate doing threshold workouts.

I really hate them.

chrisw12

Just managed a 2x20. So unbelieveably mentally hard. It's where the power meter is a God send, at least I can stare at the numbers and will them to not go down. They never go up! Yeah I know pacing pacing pacing.

Brindy

if you are getting bored in an interval its to long

Splottboy

Think "Intervals" is a misundersdtood term: It actually refers then the REST PERIOD, not the Work time, (Think of a play, or the cinema. The INTERVAL is the bit when nothing happens!)

Anyway, I feel 10 mins work time max is a realistic time, with 6 - 7 mins being more practical.
Doing about 5 - 7 of these will cream-cracker most people, if the Intensity is high enough.

Ned Overend says, 6 min intervals, up a hill are great, with a suitable recovery to lower HR.
If you can't get to within 10% of the time the first one took you, give up, you're getting too knackered. He's kicking-butt in Xterras at 55 or so, so "that'll do fur me Tommy!"

Not exactly totally scientific, but we are Human, not dancers...sorry, machines!

andy162

My cycle coach mate swears by this one & it's dead straightforward.

3x10min @ 85/90% max h/r with 5min recovery inbetween.
He recommends using the biggest gear you have so cadence is relatively low.

Towards the end of the 10min interval I'll throw in some max efforts or sprints.
You can do these in a standing position too.

This is the workout he says will give you a "bigger engine"

wheeler585

Hi,just wondering what wattage or hr, you all do your intervals at, i know everyones is different, just curious?

wheeler585

Bit like the evil hr of power

Pocket Rocket

andy162 wrote:

My cycle coach mate swears by this one & it's dead straightforward.

3x10min @ 85/90% max h/r with 5min recovery inbetween.
He recommends using the biggest gear you have so cadence is relatively low.

Towards the end of the 10min interval I'll throw in some max efforts or sprints.
You can do these in a standing position too.

This is the workout he says will give you a "bigger engine"

Sounds like it will give you 'big knee problems too"
how low is "low"?

Pokerface

Brindy wrote:

if you are getting bored in an interval its to long

That's just about the dumbest thing I've read on here since the last Bhima/Freehub thread.

andy162

Pocket Rocket wrote:

andy162 wrote:

My cycle coach mate swears by this one & it's dead straightforward.

3x10min @ 85/90% max h/r with 5min recovery inbetween.
He recommends using the biggest gear you have so cadence is relatively low.

Towards the end of the 10min interval I'll throw in some max efforts or sprints.
You can do these in a standing position too.

This is the workout he says will give you a "bigger engine"

Sounds like it will give you 'big knee problems too"
how low is "low"?

On a 53/12 I'm doing about 75-85rpm.

shockedsoshocked

andy162 wrote:

My cycle coach mate swears by this one & it's dead straightforward.

3x10min @ 85/90% max h/r with 5min recovery inbetween.
He recommends using the biggest gear you have so cadence is relatively low.

Towards the end of the 10min interval I'll throw in some max efforts or sprints.
You can do these in a standing position too.

This is the workout he says will give you a "bigger engine"

A bigger engine? If I understand it correctly, the more you grind a gear out, the less you rely on your CV system (something to do with cadence, muscle recruitment and force gradients) and instead rely on fuel already stored within the muscles.

Alex_Simmons/RST

Gav888 wrote:

Firstly, what is the best interval duration for threshold and vo2max?

The durations you quoted are all fine.

Worry less about the exact power and duration, and worry more about doing sufficient overall work at the right general levels.

Gav888 wrote:

Also for these, is it right that vo2max gains can only be made over a 2 - 3 week period and then it levels out?

No, while the time course for the adaptations relevant for increased VO2 max is relatively short, it's more in the order of 6-8 weeks.

Gav888 wrote:

And finally, for intervals such as 10 x 30sec max effort (spints) and 5 x 5m in hr zone 5, as these best used a few weeks before your goal to make sure you are in peak fitness - sort of the icing on the cake - or do you include these intervals throughout the year (excl winter base training) and progressively make gains?

Both. It depends on the primary focus of a training block.

A little of everything all the time is not a bad thing.

HR is pretty useless for intervals this short anyway. I would say that if you tried to do intervals with HR in Zone 5 for 5 minutes, it probably won't be very effective training as your actual power output would start off way too hard and then fade significantly, and subsequent intervals would become very difficult to execute at an appropriate level (despite what your HR might say).

Gav888

Alex_Simmons/RST wrote:

Gav888 wrote:

Firstly, what is the best interval duration for threshold and vo2max?

The durations you quoted are all fine.

Worry less about the exact power and duration, and worry more about doing sufficient overall work at the right general levels.

Gav888 wrote:

Also for these, is it right that vo2max gains can only be made over a 2 - 3 week period and then it levels out?

No, while the time course for the adaptations relevant for increased VO2 max is relatively short, it's more in the order of 6-8 weeks.

Gav888 wrote:

And finally, for intervals such as 10 x 30sec max effort (spints) and 5 x 5m in hr zone 5, as these best used a few weeks before your goal to make sure you are in peak fitness - sort of the icing on the cake - or do you include these intervals throughout the year (excl winter base training) and progressively make gains?

Both. It depends on the primary focus of a training block.

A little of everything all the time is not a bad thing.

HR is pretty useless for intervals this short anyway. I would say that if you tried to do intervals with HR in Zone 5 for 5 minutes, it probably won't be very effective training as your actual power output would start off way too hard and then fade significantly, and subsequent intervals would become very difficult to execute at an appropriate level (despite what your HR might say).

I agree regarding HR for Zone 5 / 6 work, it generally takes a few minutes to get up there, so I work on mph whilst on the turbo as I dont have a power meter and use speed instead of power. For example I would hold 21mph for a zone 5 workout, where a hr zone 4 speed would work out at 18mph, even though my hr hasn't reach the correct zone my legs are doing the correct-ish speed

You say a little of everything is not a bad thing, would that include zone 4 work in the base period?

Also, whilst I think of it. Ive done a basic TSS score against all my workouts and set up my weeks so they gradually increase during each period to a peak before my goal. The TSS scoring is the one I took from Friel's book which is basically time x zone, for example a 60 minute ride in zone 2 would be a TSS 120 (60 x 2). I know these don't match the proper TSS values when using a power meter but it gives me an idea of workload.

Anyway back to the question, for a threshold interval which would include a 10m warmup in zone 2, followed by 2 x 20m intervals in zone 4 with 5min rest in zone 2 would give me a TSS of 190. But a vo2max interval, such as 5 x 4 in zone 5 with 5m rest in zone 2, and 10m warmup would give me a TSS of 130.

I find the vo2max intervals harder than threshold yet they have a lower TSS score.

Would this kind of interval need a set % added to make the TSS higher as the recovery from this type of workout would be higher than a zone 4 workout? Same sort of thing when doing hill work on a turbo - big gear 75rpm, as hr is generally low making a low TSS yet the work load on your legs is high as is recovery?

Although the TSS I use gives work load, it doesnt account for recovery duration. And before you say it yes a power meter would do wonders but until they come down in price it remains on my wish list

Bronzie

Gav888 wrote:

I find the vo2max intervals harder than threshold yet they have a lower TSS score.

From my rough TSS calcs:
- 2x20 @ L4 [15min warmup / 5min recovery / 10min cooldown @ low L2] = 90TSS
- 5x5 @ L5 [15min warmup / 4x5min recovery / 10min cooldown @ low L2] = 90TSS

My understanding is that it's not unusual for higher intensity intervals to lead to a reduction in the weekly workload (and hence a drop in the long term training load (CTL)) because you typically need more recovery from such high intensity work.

Alex_Simmons/RST

Gav888 wrote:

Would this kind of interval need a set % added to make the TSS higher as the recovery from this type of workout would be higher than a zone 4 workout?

While your approach is generally the right idea (albeit less sophisticated but still applicable), the thing that's missing is the relationship between strain/stress (and the the body's physiological responses) and the effort level (power) is not a linear one, but curvlinear. So Level 5 work is not just one more step harder than Level 4 work.

In general, a threshold workout and a "VO2 max" workout of similar duration will nett about the same TSS. So that should give you a clue as to the level of curvelinearity resulting from time spent at Level 5 versus Level 4 (including accounting for recovery periods).

Gav888 wrote:

Same sort of thing when doing hill work on a turbo - big gear 75rpm, as hr is generally low making a low TSS yet the work load on your legs is high as is recovery?

No. TSS is a function of power, not the gear/cadence or HR.

If using a big gear results in you riding at a higher power than you may have done otherwise, then yes, it will result in a higher TSS.

Gav888

Alex_Simmons/RST wrote:

Gav888 wrote:

Would this kind of interval need a set % added to make the TSS higher as the recovery from this type of workout would be higher than a zone 4 workout?

While your approach is generally the right idea (albeit less sophisticated but still applicable), the thing that's missing is the relationship between strain/stress (and the the body's physiological responses) and the effort level (power) is not a linear one, but curvlinear. So Level 5 work is not just one more step harder than Level 4 work.

In general, a threshold workout and a "VO2 max" workout of similar duration will nett about the same TSS. So that should give you a clue as to the level of curvelinearity resulting from time spent at Level 5 versus Level 4 (including accounting for recovery periods).

Gav888 wrote:

Same sort of thing when doing hill work on a turbo - big gear 75rpm, as hr is generally low making a low TSS yet the work load on your legs is high as is recovery?

No. TSS is a function of power, not the gear/cadence or HR.

If using a big gear results in you riding at a higher power than you may have done otherwise, then yes, it will result in a higher TSS.

Thanks for your help Alex and others. My plan is now complete - finally!! Took me 3 weeks of studying and planning but im there now. Time to start putting it into practise

Next thing to start studying - Nutrition!!

Bronzie

Gav888 wrote:

My plan is now complete - finally!! Time to start putting it into practise

Good on ya Gav - always great to see folks on here improve their understanding of training methods - and you've asked some great questions along the way. Keep 'em coming.

The way I approach my training has changed beyond all recognition since I started hanging around here 2 years ago or so. I am damn glad we have someone as knowledgeable as Alex to point us in the right direction all the time as well. 8)

Gav888

Bronzie wrote:

Gav888 wrote:

My plan is now complete - finally!! Time to start putting it into practise

Good on ya Gav - always great to see folks on here improve their understanding of training methods - and you've asked some great questions along the way. Keep 'em coming.

The way I approach my training has changed beyond all recognition since I started hanging around here 2 years ago or so. I am damn glad we have someone as knowledgeable as Alex to point us in the right direction all the time as well. 8)

Cheers Bronzie